Strings. Pizzicare in Italian means "to pluck" and so "Pizzicato"
means "Plucked". In music the term refers to the sound produced
by plucking the strings of the members of the strings family, - the violin, the
viola, the cello, and the double bass. The sound is short and sharp
(staccato in Italian), and makes a strong contrast with the smooth flowing tone
produced with the bow.
In the computer General Midi system, pizzicato is one of the 128 GM
instruments, and can be used at any pitch, to generate the pizzicato sound of
the appropriate member of the string family, depending on the pitch of the
note. If you want the more forceful sound typically used by double bass
players in jazz and dance bands, the the "Acoustic Bass" MIDI
instrument may be preferable to the pizzicato played at a low pitch.